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Your first calculation

This tutorial takes five minutes. You define two quantities, calculate with them and copy the result. Quantus starts in Physics mode, which is what you need here; the mode is shown in the top bar.

1. Define a mass​

Click into the input and type:

m_1 = 2kg

In the formula editor, _ starts the index. Press → to leave the index before you type = 2kg. Press Enter. Quantus answers with

m1=2 kgm_{1} = 2\,\mathrm{kg}

and lists m1m_1 in the Variables panel (Ctrl+,). Because the label m_1 carries an index, the input is a definition: m1m_1 keeps its value for the whole session.

2. Calculate with it​

F = m_1 \cdot 9.81\frac{m}{s^2}

* gives a ⋅\cdot and / a fraction. Quantus shows the working:

SYMBOLICF=m1⋅9,81 ms2F = m_{1} \cdot 9{,}81\,\frac{\mathrm{m}}{\mathrm{s}^{2}}
SUBSTITUTEDF=2 kg⋅9,81 ms2F = 2\,\mathrm{kg} \cdot 9{,}81\,\frac{\mathrm{m}}{\mathrm{s}^{2}}
STEPF=19,62 kg⋅ms2F = 19{,}62\,\frac{\mathrm{kg} \cdot \mathrm{m}}{\mathrm{s}^{2}}
RESULTF=19,62 NF = 19{,}62\,\mathrm{N}

The units are multiplied with the numbers, and kg⋅m/s2\mathrm{kg \cdot m/s^2} is recognised as the newton. F has no index, so it only names the line; it is not stored.

tip

You can type a decimal point or a decimal comma (9{,}81). Results are always written with a decimal comma.

3. Units are converted for you​

v_1 = 72\frac{km}{h}
s_1 = 100m
t = \frac{s_1}{v_1}

Enter the three lines one after the other. The last one gives

t=5 st = 5\,\mathrm{s}

Quantus cancels m\mathrm{m} against km\mathrm{km} and h\mathrm{h} against s\mathrm{s} and names the result in base units.

4. Mistakes are caught​

3m + 2s

ERROR Incompatible units: m (length) and s (time) cannot be added.

5. Copy the result​

  • Ctrl+Shift+C copies the result as LaTeX.
  • Ctrl+Alt+C copies the whole calculation as an align* block, ready for your document.

Next​